1. Field of the Invention
This invention relates to a multi-function image processing system in which image data provided by an image reading unit and image data provided by external equipment are processed in a parallel mode.
2. Discussion of the Related Art
FIG. 5 shows one example of a conventional digital image processing system.
In the digital copying machine, an IIT (image input terminal) 43 reads an original with a CCD sensor or the like, and converts analog values of the resultant video signal into digital values. The digital signal is converted into binary data, being processed (for instance corrected and edited), by an IPS (image processing system). And an IOT (image output terminal) controls the on/off state of pixels according to the binary data to output a mesh-point image, thereby to reproduce the original's image.
External equipment, such as a PC (personal computer) and a facsimile machine, may be connected to the above-described digital copying machine to share the IOT 46. In this case, as shown in FIG. 5, the IOT 46 is separated from the IIT 43, and a change-over unit 45 is provided therebetween so that the IOT 46 is connected through the change-over unit 45 to the IIT 43, the PC 41 or the facsimile machine 44. Thus, the binary data provided by the PC 41 or the facsimile machine 44 can also be output similarly as in the case of the binary data provided by the IIT 43. In general the PC 41 handles code data, and therefore the PC 41 applies the binary data obtained by bit-mapping the code data to the IOT 46. The facsimile machine 44 supplies the decoded binary data to the IOT 46.
There have been available, as described above, digital image processing systems in which a printer is shared by a digital copying machine, PC, facsimile machine, etc. However, these conventional systems are not so high in productivity, because the elements thereof operate individually and exclusively.
In the conventional system comprising the digital copying machine, the PC and the facsimile machine, etc., the copying function and the print job from the external equipment are not performed in a parallel mode; that is, the jobs are processed in a first-come first-served basis. Therefore, the conventional systems suffer from a difficulty that the copying function cannot be used while a large amount of print jobs from the external equipment are being performed.